In with the new: old concrete panels on I-5 in north Seattle get the heave ho

$12.2 million preservation project replaces hundreds of concrete panels and removes crack and bumps on more than seven miles of I-5

SEATTLE – Decades of heavy use have taken a toll on Interstate 5 north of Seattle. The concrete is cracked, chipped and bumpy in many places. Now a new highway preservation project will address some of the worst areas between Northgate and Shoreline.

On Monday, Aug. 11, contractor crews from Granite Construction Company will begin a $12.2 million project to repair or replace more than 300 concrete panels between Northeast 117th Street and the King-Snohomish County line. In addition to panel replacement, crews will grind more than four miles of southbound I-5 and more than three miles northbound to remove shallow cracks, bumps and create a smoother drive with better traction.

This section of I-5 sees an average of 182,000 trips each day. The concrete panels were installed between 1962 and 1964, but were only designed to last 20 to 25 years.

“The concrete is falling apart faster than it can be patched,” said Project Engineer John Chi. “Rain, freeze and thaw cycles have also taken a toll on I-5. By replacing the worst panels and grinding other areas, we can continue to keep traffic and freight moving on this vital and aging interstate.”

Closure information The work will require nightly lane closures Sunday through Thursday nights and occasional Saturday night lane closures. Depending on the location, southbound lanes may begin closing at 7 p.m. and northbound lanes at 8 p.m. Multiple ramps will also be closed nightly beginning at 9 p.m. Drivers will follow signed detours when ramps are closed. Except on weekend mornings, all lanes and ramps will reopen by 5 a.m. daily.

The work The contractors will start by sawcutting the concrete panels. The first of the 300 panels will be lifted out and new panels poured on Wednesday, Aug. 20. Crews will work on the southbound lanes of I-5 first and then replace panels in the northbound lanes. The panel replacement work is currently scheduled to end in late October. Beginning Nov. 1, the crews will start grinding the pavement.

The project will also add a new overhead electronic sign just south of Northeast 155th Street to display travel times and messages. The contractor crews will also pave several ramps. The project is scheduled for completion in late spring 2015 when durable high visibility striping is added.

Noise Some of this work is unavoidably noisy, particularly the concrete grinding work. It is scheduled to occur during the colder months when people who live near the interstate are more likely to have their windows closed overnight. Nearby residents disturbed by the construction noise can call a 24-hour hotline to request earplugs. The hotline number is 206-440-4DOT (4368)

The project will extend the life of the freeway, reduce the need for costly and inconvenient emergency repairs and create a better driving surface for commuters.

Know before you go Drivers should know before they go by planning ahead for lane and ramp closures related to this project. WSDOT has many resources and tools for drivers: